If results have been submitted, AutoApprovalTime is the date and time the results of the assignment results are considered Approved automatically if they have not already been explicitly approved or rejected by the Requester.

#answer ⇒ String

The Worker's answers submitted for the HIT contained in a
QuestionFormAnswers document, if the Worker provides an answer. If
the Worker does not provide any answers, Answer may contain a
QuestionFormAnswers document, or Answer may be empty.

#approval_time ⇒ Time

If the Worker has submitted results and the Requester has approved
the results, ApprovalTime is the date and time the Requester
approved the results. This value is omitted from the assignment if
the Requester has not yet approved the results.

#auto_approval_time ⇒ Time

If results have been submitted, AutoApprovalTime is the date and
time the results of the assignment results are considered Approved
automatically if they have not already been explicitly approved or
rejected by the Requester. This value is derived from the
auto-approval delay specified by the Requester in the HIT. This
value is omitted from the assignment if the Worker has not yet
submitted results.